thanks for the query.
if you have been 4 days late now and your pregnancy test is negative, then it is suggested that you repeat the urine pregnancy test again at 8th post missed period day, when it would be more sensitive. If negative then pregnancy would be ruled out and then you can wait safely till 15 days post missed period to allow the menses to return naturally. The likely delay, in that case, would be due to stress-induced hormonal imbalance which is known to cause such delays. These can be allayed by following stress buster techniques and incorporating meditation and yoga in one's lifestyle.
If the menses don't resume within 15 days then you cannot for a withdrawal bleed with progestins to resume your menses.
I hope I have answered your querying detail.
Wishing good health.
These Q&A’s are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.